Further to the AR genetic disparities among various ethnic populations, other natural candidate genetic polymorphisms related to ACE2, TMPRSS2, or FURIN genes, as well as other host invasion genes such as DPP4 or PCSK3, which have been shown to differ among different population ancestries, may also provide a supplementary explanation for COVID-19 pandemic spread and progression (66–68). Here, TMPRSS2 is linked to COVID-19.